Hydrocarbon fuels, such as diesel fuel, gasoline, or the like, are useful fuels for intermittent combustion engines. However, to date, most engine designs consume fuel less efficiently than is theoretically possible. Therefore, those in the industry have recognized the potential of significantly improving fuel consumption efficiency and are continuing to develop processes that improve emissions. One area where improvements can be made includes the area of liquid fuel vaporization, particularly with respect to the above mentioned fuels. Typically, gasoline and diesel fuels must be forced into a phase where the fuel can be readily combusted. Gasoline engines, for example, require a spark to initiate combustion. Diesel fuels, on the other hand, tend to combust when subjected to heat and pressure from a combustion chamber, where the temperature increases due to compression, which allows the fuel to be converted from a liquid phase to a vapor phase.
To cite one example, in order for a reciprocating engine to generate power, the fuel must at least partially be vaporized and mixed with air rather than burned slowly in a liquid state (as the engine combustion cycle is typically too short for a slowly burning liquid fuel to burn completely before the exhaust cycle begins). This is particularly a problem with the diesel engine, as the fuel is injected into the combustion chamber in liquid spray form, is vaporized, and becomes self-ignited within the same combustion cycle. Even under normal operating conditions, diesel fuel tends to self-ignite before vaporization is complete. Further, when cold starting a diesel engine, the vaporization is even less complete, exacerbating problems associated with poor emissions. For example, soot can build up due to incomplete combustion of the fuel. Additionally, an increase in other undesirable exhaust emissions can result when the fuel is not completely consumed in the fuel combustion process.
A number of attempts have been made to remedy some of these issues. One of the more common approaches has been to include additives in the diesel fuel. Some additives have been shown to improve the cold starting performance of the engine. Other additives have been shown to improve general fuel combustion performance. However, these additives can increase the cost of already expensive fuels and may not provide optimal results.
As such, it would be desirable to provide methods and devices which lead to more complete vaporization of fuels, thereby resulting in improved fuel efficiency and reduced undesirable emissions.